1. The Field of the Invention
This invention relates to transportation equipment used to move goods such as commercial freight and household belongings.
2. The Background Art
An efficient transportation system is essential to the operation of modern industrial societies. During the past several hundred years, the most common methods of transporting goods and materials from one location to a distant location has progressed from animal-drawn wagons, to steam and diesel-driven locomotives, to today where millions of tons of goods and materials are carried upon highways by semitrailer and tractor rigs which have become familiar sights on the world's highways.
The conventional semitrailer and tractor rig (so named because the trailer relies upon the tractor to carry part of its weight) often comprises a trailer 48 feet long, 13 feet high, and 8.5 feet wide. Importantly, the total cost of operating a semitrailer and tractor rig usually varies little between the cost of operating a semitrailer which is only partially full and a semitrailer which is completely full.
Thus, by loading more items into a trailer before making a long-haul trip the cost of transporting each item to its destination will be lower than if fewer items were loaded into the trailer. In view of the foregoing, there is great incentive in the long-haul trucking industry to use the largest possible trailer and to fill the trailers to their capacity for each trip.
While much of the trucking industry is involved with the transportation of commercial freight, a significant and economically important portion of the trucking industry is concerned with the transportation of household belongings. Significantly, the above-mentioned economic considerations of completely filling a trailer before leaving on a long-haul trip also applies in the case of moving household belongings. However, the nature of moving a household belongings often makes it extremely difficult to completely fill a trailer of the type previously available in the industry, particularly on a return trip.
Like all customers of the trucking industry, household customers desire that their goods be picked up at their residence exactly at the scheduled time and delivered to their destination as soon as possible, or alternatively, at an exact date and hour. Commercial users of the trucking industry, in contrast to owners of household belongings, are often more willing and able to forgive delays in picking up and delivering fungible goods since individuals are often without furniture, cooking utensils, clothing, and personal belongings during the time that their goods are in transit. Moreover, the residential moving trade is extremely competitive and the residential customer's desire to have timely pickup and delivery works against having the lowest possible operating costs for several reasons such has those summarized below.
First, moving household goods often requires that a tractor-trailer combination be driven directly to the customer's residence. Because of government regulation or practical constraints, often times a full-sized trailer cannot be taken directly to a residence located on narrow streets or driveways, or on streets having weight limits below the weight of a loaded trailer.
Second, it is usually the case that a residential customer does not have enough household belongings to fill an entire trailer previously used in the industry. Such a trailer is 48 feet long and holds approximately 17 average rooms of furniture. Thus, unless the customer is willing to pay for the use of an entire trailer, the remaining third, half, two-thirds, or more, of the trailer must be shared with one or more other customers. Unfortunately, sharing a trailer requires that the pick-up and delivery dates may not be those desired by one or more of the customers sharing a trailer. Also, sharing a trailer often causes the time period between pick-up and delivery dates for one customer to be longer than it otherwise might be.
Third, customers are always concerned about the security of their goods. Sharing a trailer with another unknown person raises questions in customers' minds concerning the security of their goods.
Fourth, since the trailers most often used in the past to move household belongings were particularly adapted to the task, moving commercial goods in such trailers was not feasible. Thus, movers of household belongings have in the past been required to ensure that the trailer return from a distant location with another load of household belongings, but as a practical matter always partially empty. Alternatively, if the tractor and trailer were required elsewhere before a load could be arranged, the trailer made the return trip empty at great expense to the operator.
Another difficulty which is encountered when moving household goods is the cumbersome practice of building shelf decks (hereinafter sometimes referred to as "decks") and partition walls (hereinafter sometimes referred as "partitions") within cargo holding sections of trailers and truck bodies.
Decks are horizontal surfaces built within a cargo holding section to support goods placed thereon. For example, a customer may desire to move an automobile with other household goods. In such a case, the automobile can be loaded on the floor of the cargo holding section and a deck built above the automobile and goods placed thereon. In this way the high vertical space available in a cargo holding section can be used to full advantage. Moreover, decks are often built to avoid stacking goods upon each other which might cause damage to household goods.
Partition walls are built to divide a cargo holding section, such as a semitrailer, into separate compartments so that the goods of one customer are not mixed with those of other customers who must share a whole semitrailer on a long haul trips. Constructing partitions within cargo holding sections assures customers that their goods will be secure while in transit.
Prior art decks and partitions are rigged together using sheets of plywood and dimensional lumber. The plywood and dimensional lumber must always be available and carried with the trailer since the need for a deck or a partition is often unascertainable until reaching a loading site at a residence and the amount and type of household goods to be loaded is determined.
Trailers used to move household goods are regularly equipped with enclosed "pods" attached to the trailer frame under the cargo holding sections and are adapted to hold the plywood and dimensional lumber. Trailers used for hauling commercial freight are not provided with such pods and if they are used to move household belongings the material used to rig decks and partitions must be stored in the cargo carrying section thus reducing the amount of valuable room available for carrying profit generating cargo.
Thus, it will be realized that trailers adapted for hauling commercial freight are poorly equipped to haul household goods. Even further, the plywood and lumber which is used to build decks and partitions in household moving trailers is inherently weak and has a relatively short useful life compared to the strength and life of the trailers used to haul the goods.
In view of the foregoing difficulties and drawbacks found in the previous state of the art, it would be an advance in the art to provide a semitrailer which may be sectioned into a plurality of individually securable compartments and also allow the compartments to be interconnected to form a full-length continuous van body. It would also be an advance in the art to provide a semitrailer which includes a plurality of individual compartments, each compartment being capable of being off-loaded from the trailer, left at a location for loading, and later attached again to the trailer.
It would be another advance in the art to provide a plurality of cargo compartments which may be interchanged and secured to any number of properly equipped semitrailers. It would be a further advance in the art to provide a semitrailer which may be sectioned into individual compartments which are adapted to carry both household belongings and commercial freight.
It would be a still further advance in the art to provide a sectional van trailer and an accompanying tractor-mounted hoisting apparatus which allows a lone individual to both remove and secure an individual cargo compartment to the semitrailer at, for example, pick-up and drop-off locations and locations where cargo compartments are transferred from one semitrailer to another or are placed into storage. It would be yet another advance in the art to provide a semitrailer which protects its contents from contamination by dirt and moisture and securely holds the goods contained therein.
It would be a further advance in the art to provide a system and method for building decks and partitions within various cargo holding sections which is more efficient than prior art systems for building decks and partitions. It would be a still further advance in the art to provide a system and method for building decks and partitions within cargo holding sections which allows the deck and partition building materials to be stored with the cargo holding section wherever it may travel and without taking up cargo holding space. It would be yet another advance in the art to provide a system and method for building decks and partitions wherein the decks and partitions have a long usable life and are strong and durable.